1. Field of the Invention
The present invention relates to provision of navigation guidance for a mobile user. The navigation guidance may be, for example, a mobile user provided with information regarding a path of movement of another mobile user so that the mobile user may follow the other mobile user.
2. Description of the Related Art
Navigation may be required in various situations. For example, a person who wants to travel to a location from another location needs typically to do at least some navigation such as orienteering and/or selection of streets or roads in order to know which direction he/she should move to in order to arrive at the destination. Navigation aids such as compasses and/or maps and so on are known. The general concept of navigation as well as conventional navigation aids are well known, and are thus not discussed herein in more detail.
In addition to conventional maps and compasses, other navigation aids have also been developed. For instance, electronic maps have been introduced. Electronic navigator devices are also available. One of the recent developments in the field of electronic navigation aids include a handheld GPS (Global Positioning System) navigator. The GPS is based on the use of satellites. The arrangement being such that a GPS device on the ground determines its location based on signals received from the satellites of the GPS system. The GPS devices are popular amongst various user groups, and are used by both private and professional users. A similar satellite based system known as ‘Galileo’ has also been proposed.
Mobile communication systems providing mobility for the users thereof are also known. A well-known example of such mobile communication systems is the public land line mobile network (PLMN), of which cellular communications networks are an example. Another example is a mobile communication system that is based, at least partially, on use of communication satellites. Mobile communication system can be used in determining the location of a mobile user and also in provision of location information to various clients. Provision of location information by means of a mobile communications system can be implemented in various ways.
In accordance with a possibility the Global Positioning System (GPS) navigator or a similar positioning device may be integrated in or connected to a communications device of a mobile communication system. In this specification the term ‘GPS mobile station’ (GPS-MS) is used for simplicity to denote such an integrated device, the device being provided with GPS positioning functionality and a mobile station.
However, different positioning technologies than the above referenced satellite based GPS or Galileo can also be used. It is possible that the mobile device does not measure the location itself. Instead, the location determination may be accomplished, at least partially, at the network side with or without any assistance from the mobile device. Thus the position information may be provided, at least partially, by means of apparatus associated with the mobile telecommunication network. The basic principles and operation of a network based locations service are known by the skilled person, and will thus not be discussed in any greater detail. It is sufficient to note that a location service (LCS) server entity may manage the location services. The LCS server is for gathering and storing various information that may be used in provision of location information for location service clients (LCS clients).
The more recent LCS applications are such that they utilize information from various sources, such as from location measurement units of the network and mobile stations. The location service entity associated with the communication system may thus be adapted to utilize the information provided by the satellite based positioning system and/or the mobile station. The LCS based positioning may be based entirely or only partially on the information from the satellite based system and/or the mobile station.
The location service (LCS) client may make use of that location information for various services/applications. A possible application comprises a LCS client arranged to provide location information in response to a request for non-call related location information regarding a target mobile station by another mobile station. Thus it is possible for a user of a mobile station to receive information regarding the location of another i.e. target mobile station.
The information regarding the route a mobile user has taken can be used, for example, by other users for navigation purposes. Such information is believed to be useful in various occasions. For example, if a mobile user wants to follow a target mobile user to destination, it might be advantageous if such user can receive the information regarding the actions he/she needs to take to be able to follow the route taken by the target user. However, even if the user knows the final destination of the target mobile station, the user does not necessarily know the route the target user took to arrive at the destination. The user may also wish to receive additional information regarding the movements of the target mobile station.
If the target mobile user turns left or right e.g. at an intersection, the following user may not become aware that he/she should do the same. The present arrangements do not allow communication of this type of following information quick enough so that the following user can follow the target mobile user. The following user and the target mobile user may need to otherwise communicate this information from one to other, for example by establishing a voice call or sending a text message. If the following user is traveling far behind the target user, several turns or intersections may “separate” them, and communicating, keeping track of and remembering the maneuvers may prove to be difficult, especially if the following user is driving. The following user might also wish to receive other information. For example, the following user might wish to receive information if the target user has stopped (e.g. for refuelling), or is wandering about (e.g. to find an address, shop, filling station etc.) and so on.